Semiconductor device

ABSTRACT

A semiconductor device includes: a first semiconductor element including a first signal electrode; a second semiconductor element, laminated on the first semiconductor element, including a second signal electrode; a sealing body; a first signal terminal connected to the first signal electrode; and a second signal terminal connected to the second signal electrode, wherein: the first signal terminal and the second signal terminal project from the sealing body and extend in a first direction; the first signal terminal and the second signal terminal are distanced from each other in a second direction; the first signal electrode and the second signal electrode are placed at different positions in the second direction; the first signal electrode is provided closer to the first signal terminal than to the second signal terminal; and the second signal electrode is provided closer to the second signal terminal than to the first signal terminal.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Japanese Patent Application No.2018-202910 filed on Oct. 29, 2018, and Japanese Patent Application No.2018-026032 filed on Feb. 16, 2018, which are incorporated herein byreference in its entirety including the specification, drawings andabstract.

BACKGROUND 1. Technical Field

A technique disclosed in the present specification relates to asemiconductor device.

2. Description of Related Art

A semiconductor device is described in Japanese Unexamined PatentApplication Publication No. 2016-36047 (JP 2016-36047 A). Thesemiconductor device includes: a first semiconductor element; a secondsemiconductor element laminated to the first semiconductor element; asealing body configured to seal the first semiconductor element and thesecond semiconductor element; a plurality of first signal terminalsconnected to signal electrodes of the first semiconductor element; and aplurality of second signal terminals connected to signal electrodes ofthe second semiconductor element. The first signal terminals and thesecond signal terminals project from the sealing body toward a firstdirection and are distanced from each other in terms of a seconddirection that is perpendicular to the first direction.

SUMMARY

In the above semiconductor device, the signal electrodes of the firstsemiconductor element and the second semiconductor element provided in alaminated manner are close to each other. Particularly, in terms of thesecond direction where the first signal terminals and the second signalterminals are arranged, the signal electrodes of the first semiconductorelement and the signal electrodes of the second semiconductor elementare placed at the same position. On this account, it is necessary toplace, within a relatively narrow range, bonding wires for connectingthe first signal terminals to the signal electrodes of the firstsemiconductor elements and bonding wires for connecting the secondsignal terminals to the signal electrodes of the second semiconductorelement, and this can be a large restriction on the manufacturing of thesemiconductor device.

A semiconductor device according to a first aspect of the disclosureincludes: a first semiconductor element including a first signalelectrode; a second semiconductor element including a second signalelectrode, the second semiconductor element being laminated to the firstsemiconductor element; a sealing body configured to seal the firstsemiconductor element and the second semiconductor element; a firstsignal terminal connected to the first signal electrode; and a secondsignal terminal connected to the second signal electrode, wherein: thefirst signal terminal and the second signal terminal project from thesealing body and extend in a first direction; the first signal terminaland the second signal terminal are distanced from each other in a seconddirection, the second direction being a direction perpendicular to thefirst direction and a laminating direction of the first semiconductorelement and the second semiconductor element; the first signal electrodeand the second signal electrode are placed at different positions in thesecond direction; the first signal electrode is provided closer to thefirst signal terminal than to the second signal terminal; and the secondsignal electrode is provided closer to the second signal terminal thanto the first signal terminal.

In the above aspect, the signal electrode of the first semiconductorelement and the signal electrode of the second semiconductor element areplaced at different positions in terms of the second direction where thefirst signal terminal and the second signal terminal are arranged.Hereby, the signal electrode of the first semiconductor element isplaced so as to be close to the first signal terminal and the signalelectrode of the second semiconductor element is placed so as to beclose to the second signal terminal. In the above aspect, a circuitconfiguration in which the first signal terminal is connected to thesignal electrode of the first semiconductor element and a circuitconfiguration in which the second signal terminal is connected to thesignal electrode of the second semiconductor element are placed so as tobe relatively distanced from each other, thereby making it possible toeasily manufacture the semiconductor device, for example. Note that thefirst signal terminal may be connected to the signal electrode of thefirst semiconductor element via a bonding wire or other connectionmembers, or the first signal terminal may be directly connected to thesignal electrode of the first semiconductor element. This also appliesto the connection between the second signal terminal and the signalelectrode of the second semiconductor element.

In the above aspect, the first semiconductor element and the secondsemiconductor element may have the same configuration. The secondsemiconductor element may be placed at an angle 90 degrees shifted fromthe first semiconductor element.

With the above configuration, the signal electrode of the firstsemiconductor element and the signal electrode of the secondsemiconductor element can be placed at different positions in terms ofthe second direction where the first signal terminal and the secondsignal terminal are arranged. Since semiconductor elements having thesame configuration can be employed for the first semiconductor elementand the second semiconductor element, it is possible to further easilymanufacture the semiconductor device, for example.

In the above aspect, the first semiconductor element and the secondsemiconductor element may have the same configuration, and the secondsemiconductor element may be provided such that the second semiconductoris reversed back-to-front from the first semiconductor element.

With the above configuration, at least one signal electrode of aplurality of signal electrodes may be provided closer to one corner partthan to the other corner parts among four corner parts of the firstsemiconductor element, the signal electrodes being included in the firstsignal electrode.

In the above aspect, at least one signal electrode of a plurality ofsignal electrodes included in the first signal electrode may be providedin the first semiconductor element so as to be closer to one corner partthan to other corner parts among four corner parts of the firstsemiconductor element.

With the above configuration, when the second semiconductor element isrotated by 90 degrees or reversed back-to-front from the firstsemiconductor element, the signal electrode of the first semiconductorelement and the signal electrode of the second semiconductor element canbe sufficiently distanced from each other in the second direction (thatis, a direction where the first signal terminal and the second signalterminal are arranged).

In the above aspect, the signal electrode provided closer to the onecorner part than to the other corner parts may be provided symmetricallywith respect to a bisector of the one corner part.

With the above configuration, when the second semiconductor element isrotated by 90 degrees or reversed back-to-front from the firstsemiconductor element, the signal electrode of the first semiconductorelement and the signal electrode of the second semiconductor element areplaced symmetrically.

In the above aspect, all the signal electrodes included in the firstsignal electrode may be provided closer to the one corner part than tothe other corner parts among the four corner parts of the firstsemiconductor element.

With the above configuration when the second semiconductor element isrotated by 90 degrees or reversed back-to-front from the firstsemiconductor element, all the signal electrodes of the firstsemiconductor element and all the signal electrodes of the secondsemiconductor element are not placed at the same position in terms ofthe second direction.

In the above aspect, the first semiconductor element and the secondsemiconductor element may have the same configuration; a plurality ofsignal electrodes having the same function may be provided, in the firstsemiconductor element, symmetrically with respect to a center line ofthe first semiconductor element in the second direction; and a pluralityof signal electrodes having the same function may be provided, in thesecond semiconductor element, symmetrically with respect to a centerline of the second semiconductor element in the second direction.

With the above configuration, the signal electrodes of the firstsemiconductor element and the signal electrodes of the secondsemiconductor element can be placed at different positions in terms ofthe second direction where the first signal terminal and the secondsignal terminal are arranged.

In the above aspect, the first semiconductor element and the secondsemiconductor element may be placed at different positions in the seconddirection. That is, the first semiconductor element and the secondsemiconductor element may not necessarily be provided on the sameposition. The first signal terminal may be shifted from the secondsignal terminal by shifting the first semiconductor element from thesecond semiconductor element.

In the above aspect, the first signal terminal and the second signalterminal may be placed at the same position in the laminating direction.

With the above configuration, the sealing body can be easily molded, forexample.

In the above aspect, the semiconductor device may further include apower terminal electrically connected to the first semiconductorelement. The power terminal may be placed on the opposite side from thefirst signal terminal across the sealing body.

With the above configuration, at the time when the sealing body ismolded in a manufacturing stage of the semiconductor device, forexample, the first semiconductor element and the second semiconductorelement can be supported stably by the first signal terminal and thesecond signal terminal, and the power terminal placed on the oppositeside from the first signal terminal and the second signal terminal.

In the above aspect, the first semiconductor element and the secondsemiconductor element may have the same configuration; the firstsemiconductor element may include a plurality of signal electrodesarranged in line; the second semiconductor element may include aplurality of signal electrodes arranged in line; and at least either oneof a first arrangement direction and a second arrangement direction mayform an angle with respect to the second direction, the firstarrangement direction being an arrangement direction of the signalelectrodes in the first semiconductor element, and the secondarrangement direction being an arrangement direction of the signalelectrodes in the second semiconductor element.

In the above aspect, the first arrangement direction and the secondarrangement direction may not be parallel to each other and formrespective angles with respect to the second direction.

In the above aspect, each of the first arrangement direction and thesecond arrangement direction may form an angle of 45 degrees to thesecond direction.

BRIEF DESCRIPTION OF THE DRAWINGS

Features, advantages, and technical and industrial significance ofexemplary embodiments of the disclosure will be described below withreference to the accompanying drawings, in which like numerals denotelike elements, and wherein:

FIG. 1 illustrates a plan view of a semiconductor device 10 ofEmbodiment 1;

FIG. 2 schematically illustrates a sectional structure of thesemiconductor device 10 of Embodiment 1;

FIG. 3 illustrates an exploded view of the semiconductor device 10 ofEmbodiment 1;

FIG. 4 illustrates semiconductor elements 20 a, 20 b in thesemiconductor device 10 of Embodiment 1;

FIG. 5 schematically illustrates a main feature of the semiconductordevice 10 of Embodiment 1;

FIG. 6A illustrates a first example of modifications of thesemiconductor elements 20 a and 20 b;

FIG. 6B illustrates a second example of modifications of thesemiconductor elements 20 a and 20 b;

FIG. 6C illustrates a third example of modifications of thesemiconductor elements 20 a and 20 b;

FIG. 7 illustrates a plan view of a semiconductor device 110 ofEmbodiment 2;

FIG. 8 schematically illustrates a sectional structure of thesemiconductor device 110 of Embodiment 2;

FIG. 9 schematically illustrates a main feature of the semiconductordevice 110 of Embodiment 2;

FIG. 10 schematically illustrates a main feature of a modification ofthe semiconductor device 110 of Embodiment 2;

FIG. 11 schematically illustrates a main feature of a semiconductordevice 210 of Embodiment 3;

FIG. 12 schematically illustrates a main feature of a semiconductordevice 310 of Embodiment 4;

FIG. 13A illustrates a forth example of modifications of thesemiconductor elements 20 a and 20 b;

FIG. 13B illustrates a fifth example of modifications of thesemiconductor elements 20 a and 20 b;

FIG. 13C illustrates a sixth example of modifications of thesemiconductor elements 20 a and 20 b;

FIG. 13D illustrates a seventh example of modifications of thesemiconductor elements 20 a and 20 b;

FIG. 14 schematically illustrates a sectional structure of asemiconductor device 410 of Embodiment 5;

FIG. 15 schematically illustrates a sectional structure of asemiconductor device 510 of Embodiment 6;

FIG. 16 illustrates a plan view of a semiconductor device 610 ofEmbodiment 7;

FIG. 17 schematically illustrates a sectional structure of thesemiconductor device 610 of Embodiment 7;

FIG. 18 illustrates a plan view of a semiconductor device 710 ofEmbodiment 8;

FIG. 19 schematically illustrates a sectional structure of thesemiconductor device 710 of Embodiment 8;

FIG. 20 illustrates a plan view of a semiconductor device 810 ofEmbodiment 9;

FIG. 21 illustrates an exploded view of the semiconductor device 810 ofEmbodiment 9; and

FIG. 22 schematically illustrates a structure of a semiconductor device810′ of one modification.

DETAILED DESCRIPTION OF EMBODIMENTS Embodiment 1

A semiconductor device 10 of Embodiment 1 will be described withreference to the drawings. The semiconductor device 10 of the presentembodiment is a power semiconductor device and can be used for a powerconverter circuit such as a converter or an inverter in anelectrically-driven vehicle such as an electric vehicle, a hybridvehicle, and a fuel-cell vehicle, for example. Note that the purpose ofthe semiconductor device 10 is not limited particularly. Thesemiconductor device 10 can be widely used for various devices andcircuits.

As illustrated in FIGS. 1 to 3, the semiconductor device 10 includes afirst semiconductor element 20 a, a second semiconductor element 20 b, asealing body 12, and a plurality of terminals 14, 15, 16, 18, 19. Thefirst semiconductor element 20 a and the second semiconductor element 20b are provided in a laminated manner and sealed inside the sealing body12. The first semiconductor element 20 a and the second semiconductorelement 20 b are semiconductor elements having the same configuration.The second semiconductor element 20 b is placed at an angle 90 degreesshifted from the first semiconductor element 20 a. The sealing body 12is made of a material having an insulating property and may be made ofthermosetting resin such as epoxy resin, for example, but the sealingbody 12 is not limited in particular. Each of the terminals 14, 15, 16,18, 19 extends inwardly from outside the sealing body 12 so as to beelectrically connected to at least either one of the first semiconductorelement 20 a and the second semiconductor element 20 b inside thesealing body 12. The terminals 14, 15, 16, 18, 19 can be made of aconductive material such as metal, and the terminals 14, 15, 16, 18, 19are made of copper in the present embodiment, although the terminals 14,15, 16, 18, 19 are not limited in particular.

The terminals 14, 15, 16, 18, 19 include an upper power terminal 14 forelectric power, a lower power terminal 16 for electric power, anintermediate power terminal 15 for electric power, a plurality of firstsignal terminals 18 for signal, and a plurality of second signalterminals 19 for signal. When the first signal terminals 18 and thesecond signal terminals 19 are planarly viewed along a laminatingdirection (a Z-direction in the figure) of the first semiconductorelement 20 a and the second semiconductor element 20 b, the first signalterminals 18 and the second signal terminals 19 project from the sealingbody 12 toward a first direction (an X-direction in the figure) and aredistanced from each other in a second direction (a Y-direction in thefigure) that is perpendicular to the first direction (the X-direction).The first signal terminals 18 extend generally in parallel to each otheralong the first direction (the X-direction) and are arranged at regularintervals along the second direction (the Y-direction). Similarly, thesecond signal terminals 19 extend generally in parallel to each otheralong the first direction (the X-direction) and are arranged at regularintervals along the second direction (the Y-direction). Note that“generally parallel” as used in the present specification indicates thatan angle deviation of 10 degrees or less from an exact parallel state isallowable. Although the first signal terminals 18 and the second signalterminals 19 are not limited in particular, the first signal terminals18 and the second signal terminals 19 are placed on the same plane atleast at a position where the first signal terminals 18 and the secondsignal terminals 19 pass through a surface of the sealing body 12.Further, as indicated by a broken line in FIG. 3, in a manufacturingstage of the semiconductor device 10, the first signal terminals 18 maybe fixed to (or formed integrally with) an intermediate conductor plate32, as a lead frame. Similarly, the second signal terminals 19 may befixed to (or formed integrally with) a lower conductor plate 34, as alead frame.

The upper power terminal 14, the lower power terminal 16, and theintermediate power terminal 15 are placed on the opposite side from thefirst signal terminals 18 and the second signal terminals 19 across thesealing body 12. When the upper power terminal 14, the lower powerterminal 16, and the intermediate power terminal 15 are planarly viewedalong the laminating direction (the Z-direction), the upper powerterminal 14, the lower power terminal 16, and the intermediate powerterminal 15 project from the sealing body 12 toward the oppositedirection from the first direction (the X-direction) and are distancedfrom each other in the second direction (the Y-direction in the figure).Since the upper power terminal 14, the lower power terminal 16, and theintermediate power terminal 15 are terminals where a relatively largecurrent flows, the upper power terminal 14, the lower power terminal 16,and the intermediate power terminal 15 are formed wider than the firstsignal terminals 18 and the second signal terminals 19 and have a largersectional area than those of the first signal terminals 18 and thesecond signal terminals 19. Although the upper power terminal 14, thelower power terminal 16, and the intermediate power terminal 15 are notlimited in particular, the upper power terminal 14, the lower powerterminal 16, and the intermediate power terminal 15 are placed on thesame plane at least at a position where the upper power terminal 14, thelower power terminal 16, and the intermediate power terminal 15 pass thesurface of the sealing body 12.

The first semiconductor element 20 a and the second semiconductorelement 20 b are power semiconductor elements and have the sameconfiguration. As illustrated in FIG. 4, each of the semiconductorelements 20 a and 20 b includes a semiconductor substrate 22, afront-surface electrode 24, a back-surface electrode 26, and a pluralityof signal electrodes 28. The front-surface electrode 24 is provided on afront surface of the semiconductor substrate 22, and the back-surfaceelectrode 26 is provided on a back surface of the semiconductorsubstrate 22. That is, the semiconductor element 20 a, 20 b is avertical semiconductor element including the electrodes 24, 26 providedin a pair across the semiconductor substrate 22. The semiconductorelement 20 a, 20 b has a generally rectangular plate shape and has fourcorner parts 21 v, 21 w, 21 x, 21 y.

The signal electrodes 28 are placed on a front surface side of thesemiconductor substrate 22, similarly to the front-surface electrode 24.The signal electrodes 28 are provided in a close manner at one cornerpart 21 v in the semiconductor element 20 a, 20 b. In the presentembodiment, the signal electrodes 28 are provided symmetrically across abisector of the one corner part 21 v, although the signal electrodes 28are not limited in particular. Further, all the signal electrodes 28 areplaced so as to be closest to the one corner part 21 v from among thefour corner parts 21 v, 21 w, 21 x, 21 y in the semiconductor element 20a, 20 b. That is, the signal electrodes 28 are all provided within arange of one fourth of the semiconductor element 20 a, 20 b.

As an example, the semiconductor element 20 a, 20 b in the presentembodiment is a reverse conducting-insulated gate bipolar transistor(RC-IGBT), and the semiconductor substrate 22 is made of silicon (Si).In the semiconductor element 20 a, 20 b, the front-surface electrode 24functions as an emitter electrode, and the back-surface electrode 26functions as a collector electrode. Further, the signal electrodes 28include, for example, a gate signal electrode 28 a, a sense emitterelectrode 28 b, and a kelvin emitter electrode 28 c. Note that thenumber of signal electrodes 28 and their functions are not limited tothose exemplified in the present embodiment. As another example, thesemiconductor element 20 a, 20 b may be other types of powersemiconductor elements such as a metal-oxide-semiconductor field-effecttransistor (MOSFET). Further, a material for forming the semiconductorsubstrate 22 is not limited to silicon and may be other semiconductorssuch as silicon carbide (SiC) or nitride semiconductor, for example.Further, the semiconductor element 20 a, 20 b may be replaced with acombination of two or more semiconductor elements such as a combinationof a diode and an IGBT (or MOSFET).

Respective first signal terminals 18 are connected to respective signalelectrodes 28 of the first semiconductor element 20 a inside the sealingbody 12. As an example, in the present embodiment, the first signalterminals 18 are directly soldered to the signal electrodes 28. Notethat, as another example, the first signal terminals 18 may be connectedto the signal electrodes 28 by wire bonding, for example. How to connectto the first signal terminals 18 to the signal electrodes 28 is notlimited in particular. Similarly, respective second signal terminals 19are connected to respective signal electrodes 28 of the secondsemiconductor element 20 b inside the sealing body 12. How to connect tothe second signal terminals 19 to the signal electrodes 28 is also notlimited in particular. Note that, as another example, one first signalterminal 18 or second signal terminal 19 may be connected to two or moresignal electrodes 28 of the first semiconductor element 20 a and/or thesecond semiconductor element 20 b. Alternatively, two or more firstsignal terminals 18 and/or second signal terminals 19 may be connectedto one signal electrode 28 of the first semiconductor element 20 a orthe second semiconductor element 20 b.

Referring back to FIGS. 1 to 3, the semiconductor device 10 includes anupper conductor plate 30, the intermediate conductor plate 32, and thelower conductor plate 34. The upper conductor plate 30 is a generallyplate-shaped member and includes a top face 30 a and a bottom face 30 b.The back-surface electrode 26 of the first semiconductor element 20 a isjoined to the bottom face 30 b of the upper conductor plate 30. Theupper power terminal 14 is connected to the upper conductor plate 30.Hereby, the back-surface electrode 26 of the first semiconductor element20 a is electrically connected to the upper power terminal 14 via theupper conductor plate 30. As an example, in the present embodiment, theupper power terminal 14 is provided integrally with the upper conductorplate 30. The top face 30 a of the upper conductor plate 30 is exposedon a top face 12 a of the sealing body 12. Hereby, the upper conductorplate 30 also functions as a heat sink that releases heat of the twosemiconductor elements 20 a, 20 b to outside.

The intermediate conductor plate 32 is a generally plate-shaped memberand includes a top face 32 a and a bottom face 32 b. The intermediateconductor plate 32 is placed between the first semiconductor element 20a and the second semiconductor element 20 b and faces the bottom face 30b of the upper conductor plate 30 across the first semiconductor element20 a. The front-surface electrode 24 of the first semiconductor element20 a is joined to the top face 32 a of the intermediate conductor plate32. Further, the back-surface electrode 26 of the second semiconductorelement 20 b is joined to the bottom face 32 b of the intermediateconductor plate 32. Hereby, the two semiconductor elements 20 a, 20 bare serially-connected to each other via the intermediate conductorplate 32. The intermediate power terminal 15 is connected to theintermediate conductor plate 32. As an example, in the presentembodiment, the intermediate power terminal 15 is provided integrallywith the intermediate conductor plate 32.

The lower conductor plate 34 is a generally plate-shaped member andincludes a top face 34 a and a bottom face 34 b. The lower conductorplate 34 faces the bottom face 32 b of the intermediate conductor plate32 across the second semiconductor element 20 b. The front-surfaceelectrode 24 of the second semiconductor element 20 b is joined to thetop face 34 a of the lower conductor plate 34. The lower power terminal16 is connected to the lower conductor plate 34. Hereby, thefront-surface electrode 24 of the second semiconductor element 20 b iselectrically connected to the lower power terminal 16 via the lowerconductor plate 34. As an example, in the present embodiment, the lowerpower terminal 16 is provided integrally with the lower conductor plate34. The bottom face 34 b of the lower conductor plate 34 is exposed on abottom face 12 b of the sealing body 12. Hereby, the lower conductorplate 34 also functions as a heat sink that releases heat of the twosemiconductor elements 20 a, 20 b to outside.

With such a configuration, the semiconductor device 10 of the presentembodiment has a circuit structure in which two RC-IGBTs areserially-connected between the upper power terminal 14 and the lowerpower terminal 16 and the intermediate power terminal 15 is connectedbetween the two RC-IGBTs. Accordingly, the semiconductor device 10 canconstitute upper and lower arms in a power converter circuit such as aDC-DC converter or an inverter, for example. Note that a plurality offirst semiconductor elements 20 a may be provided in parallel betweenthe upper conductor plate 30 and the intermediate conductor plate 32,and a plurality of second semiconductor elements 20 b may be provided inparallel between the intermediate conductor plate 32 and the lowerconductor plate 34. Hereby, a rated current (allowable current) of thesemiconductor device 10 can be raised, for example.

In the semiconductor device 10 of the present embodiment, asschematically illustrated in FIG. 5, the second semiconductor element 20b is placed with a posture rotated by 90 degrees from the firstsemiconductor element 20 a. Hereby, in terms of the second direction(the Y-direction) where the first signal terminals 18 and the secondsignal terminals 19 are arranged, the signal electrodes 28 of the firstsemiconductor element 20 a and the signal electrodes 28 of the secondsemiconductor element 20 b are placed at different positions. As aresult, the signal electrodes 28 of the first semiconductor element 20 aare placed so as to be close to the first signal terminals 18 and thesignal electrodes 28 of the second semiconductor element 20 b are placedso as to be close to the second signal terminals 19. In such aconfiguration, a circuit configuration in which the first signalterminals 18 are connected to the signal electrodes 28 of the firstsemiconductor element 20 a and a circuit configuration in which thesecond signal terminals 19 are connected to the signal electrodes 28 ofthe second semiconductor element 20 b are placed so as to be relativelydistanced from each other, thereby making it possible to easilymanufacture the semiconductor device 10, for example. Note that thefirst signal terminals 18 may be connected to the signal electrodes 28of the first semiconductor element 20 a via bonding wires or otherconnection members (e.g., a circuit substrate). Alternatively, like thepresent embodiment, the first signal terminals 18 may be directlyconnected to the signal electrodes 28 of the first semiconductor element20 a. This also applies to the connection between the second signalterminals 19 and the signal electrodes 28 of the second semiconductorelement 20 b.

In the semiconductor device 10 of the present embodiment, semiconductorelements having the same configuration are employed for the firstsemiconductor element 20 a and the second semiconductor element 20 b. Asdescribed above, in the semiconductor element 20 a, 20 b, the signalelectrodes 28 are provided symmetrically across the bisector of the onecorner part 21 v (see FIG. 4). In such a configuration, when the secondsemiconductor element 20 b is located at an angle of 90 degrees shiftedfrom the first semiconductor element 20 a, the signal electrodes 28 ofthe first semiconductor element 20 a and the signal electrodes 28 of thesecond semiconductor element 20 b are placed symmetrically. Hereby, byconstituting the first signal terminals 18 and the second signalterminals 19 symmetrically, for example, the first signal terminals 18and the second signal terminals. 19 can have the same electricalspecification or similar electrical specifications to each other.

Further, in the semiconductor element 20 a, 20 b of the presentembodiment, the signal electrodes 28 are all placed so as to be closestto the one corner part 21 v from among the four corner parts 21 v, 21 w,21 x, 21 y of the semiconductor element 20 a, 20 b (see FIG. 4). In sucha configuration, when the second semiconductor element 20 b is rotatedby 90 degrees from the first semiconductor element 20 a, all the signalelectrodes 28 of the first semiconductor element 20 a and all the signalelectrodes 28 of the second semiconductor element 20 b are not placed atthe same position in the second direction (the Y-direction). Note that,in the present embodiment, in terms of the second direction (theY-direction), the first semiconductor element 20 a and the secondsemiconductor element 20 b are placed at different positions. With sucha configuration, a distance between the signal electrodes 28 of thefirst semiconductor element 20 a and the signal electrodes 28 of thesecond semiconductor element 20 b can be made larger.

As another example, the first semiconductor element 20 a and the secondsemiconductor element 20 b may be placed at the same position in termsof the second direction (the Y-direction). Further, in terms of thefirst direction (the X-direction), the first semiconductor element 20 aand the second semiconductor element 20 b may be placed at the sameposition or may be placed at different positions. However, in order toavoid upsizing of the semiconductor device 10, in some embodiments,respective areas of the two semiconductor elements 20 a, 20 b overlapwith each other by 50% or more, 75% or more, or 90% or more when thesemiconductor elements 20 a, 20 b are planarly viewed along thelaminating direction (the Z-direction) of the semiconductor elements 20a, 20 b.

In the semiconductor device 10 of the present embodiment, the firstsignal terminals 18 and the second signal terminals 19 are placed on afirst side of the sealing body 12, and three power terminals 14, 15, 16are placed on a second side of the sealing body 12. With such aconfiguration, at the time when the sealing body 12 is molded in amanufacturing stage of the semiconductor device 10, for example, thefirst semiconductor element 20 a and the second semiconductor element 20b can be supported stably by the first signal terminals 18 and thesecond signal terminals 19, and the power terminals 14, 15, 16 placed onthe opposite side from the first signal terminals 18 and the secondsignal terminals 19.

The number and position of signal electrodes 28 included in the firstsemiconductor element 20 a and the second semiconductor element 20 b andthe function of the signal electrodes 28 are not limited in particular.For example, as illustrated in FIG. 6A, the first semiconductor element20 a and/or the second semiconductor element 20 b may include only onesignal electrode 28 a. Alternatively, as illustrated in FIG. 6B, thefirst semiconductor element 20 a and/or the second semiconductor element20 b may include two signal electrodes 28 a, 28 b. Alternatively, asillustrated in FIG. 6C, the first semiconductor element 20 a and/or thesecond semiconductor element 20 b may include three signal electrodes 28a, 28 b, 28 c (or more).

Embodiment 2

With reference to FIGS. 7 to 9, the following describes a semiconductordevice 110 of Embodiment 2. The semiconductor device 110 of the presentembodiment is different from the semiconductor device 10 of Embodiment 1in that the posture of the second semiconductor element 20 b is changed.More specifically, the second semiconductor element 20 b is placed so asto be reversed from the first semiconductor element 20 a, and this pointis a difference from the semiconductor device 10 of Embodiment 1. Otherpoints of the semiconductor device 110 of Embodiment 2 are the same asthose of the semiconductor device 10 of Embodiment 1. Accordingly, thesame reference sign is assigned to the same constituent and a redundantdescription is omitted. Further, the modifications described inEmbodiment 1 can be also employed in the present embodiment.

The posture of the first semiconductor element 20 a is not changed fromthat in the semiconductor device 10 of Embodiment 1. Accordingly, theback-surface electrode 26 of the first semiconductor element 20 a isjoined to the bottom face 30 b of the upper conductor plate 30, and thefront-surface electrode 24 of the first semiconductor element 20 a isjoined to the top face 32 a of the intermediate conductor plate 32. Onthe other hand, the posture of the second semiconductor element 20 b isreversed from that in the semiconductor device 10 of Embodiment 1.Accordingly, the front-surface electrode 24 of the second semiconductorelement 20 b is joined to the bottom face 32 b of the intermediateconductor plate 32, and the back-surface electrode 26 of the secondsemiconductor element 20 b is joined to the top face 34 a of the lowerconductor plate 34.

In the above configuration, the semiconductor device 110 of the presentembodiment has a circuit structure in which two RC-IGBTs areserially-connected when the upper power terminal 14 and the lower powerterminal 16 are connected to each other. Such a circuit structure canconstitute an upper arm or a lower arm in a power converter circuit suchas a DC-DC converter or an inverter, for example. Note that a pluralityof first semiconductor elements 20 a may be provided in parallel betweenthe upper conductor plate 30 and the intermediate conductor plate 32,and a plurality of second semiconductor elements 20 b may be provided inparallel between the intermediate conductor plate 32 and the lowerconductor plate 34. Hereby, a rated current (allowable current) of thesemiconductor device 110 can be raised, for example.

In the semiconductor device 110 of the present embodiment, asschematically illustrated in FIG. 9, the second semiconductor element 20b is placed such that the second semiconductor element 20 b is reversedback-to-front from the first semiconductor element 20 a. Hereby, interms of the second direction (the Y-direction) where the first signalterminals 18 and the second signal terminals 19 are arranged, the signalelectrodes 28 of the first semiconductor element 20 a and the signalelectrodes 28 of the second semiconductor element 20 b are placed atdifferent positions. As a result, the signal electrodes 28 of the firstsemiconductor element 20 a are placed so as to be close to the firstsignal terminals 18 and the signal electrodes 28 of the secondsemiconductor element 20 b are placed so as to be close to the secondsignal terminals 19. In such a configuration, a circuit configuration inwhich the first signal terminals 18 are connected to the signalelectrodes 28 of the first semiconductor element 20 a and a circuitconfiguration in which the second signal terminals 19 are connected tothe signal electrodes 28 of the second semiconductor element 20 b areplaced so as to be relatively distanced from each other, thereby makingit possible to easily manufacture the semiconductor device 110, forexample. Note that the first signal terminals 18 may be connected to thesignal electrodes 28 of the first semiconductor element 20 a via bondingwires or other connection members (e.g., a circuit substrate).Alternatively, like the present embodiment, the first signal terminals18 may be directly connected to the signal electrodes 28 of the firstsemiconductor element 20 a. This also applies to the connection betweenthe second signal terminals 19 and the signal electrodes 28 of thesecond semiconductor element 20 b.

In the semiconductor device 110 of the present embodiment, semiconductorelements having the same configuration are employed for the firstsemiconductor element 20 a and the second semiconductor element 20 b. Asdescribed in Embodiment 1, in the semiconductor element 20 a, 20 b, thesignal electrodes 28 are provided symmetrically across the bisector ofthe one corner part 21 v (see FIG. 4). In such a configuration, when thesecond semiconductor element 20 b is reversed back-to-front from thefirst semiconductor element 20 a, the signal electrodes 28 of the firstsemiconductor element 20 a and the signal electrodes 28 of the secondsemiconductor element 20 b are placed symmetrically. Hereby, byconstituting the first signal terminals 18 and the second signalterminals 19 symmetrically, for example, the first signal terminals 18and the second signal terminals 19 can have the same electricalspecification or similar electrical specifications to each other.

Further, in the semiconductor element 20 a, 20 b of the presentembodiment, the signal electrodes 28 are all placed so as to be closestto the one corner part 21 v from among the four corner parts 21 v, 21 w,21 x, 21 y of the semiconductor element 20 a, 20 b (see FIG. 4). In sucha configuration, when the second semiconductor element 20 b is reversedback-to-front from the first semiconductor element 20 a, all the signalelectrodes 28 of the first semiconductor element 20 a and all the signalelectrodes 28 of the second semiconductor element 20 b are not placed atthe same position in the second direction (the Y-direction). Note that,in the present embodiment, in terms of the second direction (theY-direction), the first semiconductor element 20 a and the secondsemiconductor element 20 b are placed at different positions. With sucha configuration, a distance between the signal electrodes 28 of thefirst semiconductor element 20 a and the signal electrodes 28 of thesecond semiconductor element 20 b can be made larger.

In the semiconductor element 20 a, 20 b, the number and placement ofsignal electrodes 28 may be changed variously. That is, thesemiconductor device 110 of the present embodiment also can employvarious semiconductor elements 20 a, 20 b as illustrated in FIGS. 6A to6C. Further, as illustrated in FIG. 10, as long as one or more signalelectrodes 28 are provided in a close manner at the one corner part 21 vin the semiconductor element 20 a, 20 b, the one or more signalelectrodes 28 may not necessarily be provided symmetrically across thebisector of the corner part 21 v. Even in this case, when the secondsemiconductor element 20 b is placed with a posture reversedback-to-front from the first semiconductor element 20 a, the signalelectrodes 28 of the first semiconductor element 20 a and the signalelectrodes 28 of the second semiconductor element 20 b are placed atdifferent positions from each other in terms of the second direction(the Y-direction) where the first signal terminals 18 and the secondsignal terminals 19 are arranged.

In the present embodiment, the first semiconductor element 20 a and thesecond semiconductor element 20 b are placed so that the front-surfaceelectrode 24 of the first semiconductor element 20 a and thefront-surface electrode 24 of the second semiconductor element 20 b faceeach other. In other words, the first semiconductor element 20 a and thesecond semiconductor element 20 b are placed so that the back-surfaceelectrode 26 of the first semiconductor element 20 a and theback-surface electrode 26 of the second semiconductor element 20 b faceoutwardly. This is because the area of the back-surface electrode 26 islarger than the area of the front-surface electrode 24, and theback-surface electrode 26 is superior to the front-surface electrode 24in terms of a heat dissipation property. As described earlier, the upperconductor plate 30 and the lower conductor plate 34 function as a heatsink. From this point, when the back-surface electrodes 26 of the firstsemiconductor element 20 a and the second semiconductor element 20 b areeach connected to a corresponding one of the upper conductor plate 30and the lower conductor plate 34, heat of the first semiconductorelement 20 a and the second semiconductor element 20 b can be releasedoutside efficiently.

Note that, as another example, the first semiconductor element 20 a andthe second semiconductor element 20 b may be placed so that theback-surface electrode 26 of the first semiconductor element 20 a andthe back-surface electrode 26 of the second semiconductor element 20 bface each other. Further, since the intermediate conductor plate 32 doesnot function as a heat sink, the thickness of the intermediate conductorplate 32 may be reduced in comparison with the thicknesses of the upperconductor plate 30 and the lower conductor plate 34. This makes itpossible to achieve downsizing of the semiconductor device 110. Thisalso applies to the semiconductor device 10 of Embodiment 1.

Embodiment 3

With reference to FIG. 11, the following describes a semiconductordevice 210 of Embodiment 3. The semiconductor device 210 of the presentembodiment is different from the semiconductor device 10 of Embodiment 1in that the configuration of the first semiconductor element 20 a andthe second semiconductor element 20 b is changed. Note that, in thepresent embodiment, semiconductor elements having the same configurationare also employed for the first semiconductor element 20 a and thesecond semiconductor element 20 b. Note that the first semiconductorelement 20 a and the second semiconductor element 20 b are not placed atan angle of 90 degrees shifted from each other and are, placed with thesame posture.

In the first semiconductor element 20 a and the second semiconductorelement 20 b of the present embodiment, the signal electrodes 28 arearranged along the second direction (the Y-direction) where the firstsignal terminals 18 and the second signal terminals 19 are arranged. Thesignal electrodes 28 include two gate signal electrodes 28 a, two senseemitter electrodes 28 b, and one kelvin emitter electrode 28 c. Thekelvin emitter electrode 28 c is placed at the center of thesemiconductor element 20 a, 20 b in terms of the Y-direction. The twogate signal electrodes 28 a and the two sense emitter electrodes 28 bare placed symmetrically across the kelvin emitter electrode 28 c.

As described above, in each of the first semiconductor element 20 a andthe second semiconductor element 20 b of the present embodiment, thesignal electrodes 28 a, 28 b having the same function are placedbilaterally symmetrically. Even in such a configuration, three signalelectrodes 28 connected to the first signal terminals 18, among thesignal electrodes 28 of the first semiconductor element 20 a, are placedso as to be close to the first signal terminals 18. Further, threesignal electrodes 28 connected to the second signal terminals 19, amongthe signal electrodes 28 of the second semiconductor element 20 b, areplaced so as to be close to the second signal terminals 19. Accordingly,a circuit configuration in which the first signal terminals 18 areconnected to the signal electrodes 28 of the first semiconductor element20 a and a circuit configuration in which the second signal terminals 19are connected to the signal electrodes 28 of the second semiconductorelement 20 b are placed so as to be relatively distanced from eachother, thereby making it possible to easily manufacture thesemiconductor device 210, for example. Note that the first signalterminals 18 may be connected to the signal electrodes 28 of the firstsemiconductor element 20 a via bonding wires or other connection members(e.g., a circuit substrate). Alternatively, the first signal terminals18 may be directly connected to the signal electrodes 28 of the firstsemiconductor element 20 a. This also applies to the connection betweenthe second signal terminals 19 and the signal electrodes 28 of thesecond semiconductor element 20 b.

Embodiment 4

With reference to FIG. 12, the following describes a semiconductordevice 310 of Embodiment 4. The semiconductor device 310 of the presentembodiment is different from the semiconductor device 110 of Embodiment2 in that the configuration of the first semiconductor element 20 a andthe second semiconductor element 20 b is changed. Note that, in thepresent embodiment, semiconductor elements having the same configurationare also employed for the first semiconductor element 20 a and thesecond semiconductor element 20 b. The second semiconductor element 20 bis placed such that the second semiconductor element 20 b is reversedback-to-front from the first semiconductor element 20 a.

In the first semiconductor element 20 a and the second semiconductorelement 20 b of the present embodiment, the signal electrodes 28 arearranged along the second direction (the Y-direction) where the firstsignal terminals 18 and the second signal terminals 19 are arranged. Thesignal electrodes 28 include two gate signal electrodes 28 a, two senseemitter electrodes 28 b, and one kelvin emitter electrode 28 c. Thekelvin emitter electrode 28 c is placed at the center of thesemiconductor element 20 a, 20 b in terms of the Y-direction. The twogate signal electrodes 28 a and the two sense emitter electrodes 28 bare placed symmetrically across the kelvin emitter electrode 28 c. Thatis, the semiconductor device 310 of the present embodiment is configuredsuch that the first semiconductor element 20 a and the secondsemiconductor element 20 b as described in Embodiment 3 are employed inthe semiconductor device 110 of Embodiment 2.

As described above, in each of the first semiconductor element 20 a andthe second semiconductor element 20 b of the present embodiment, thesignal electrodes 28 a, 28 b having the same function are placedbilaterally symmetrically. Even in such a configuration, three signalelectrodes 28 connected to the first signal terminals 18, among thesignal electrodes 28 of the first semiconductor element 20 a, are placedso as to be close to the first signal terminals 18. Further, threesignal electrodes 28 connected to the second signal terminals 19, amongthe signal electrodes 28 of the second semiconductor element 20 b, areplaced so as to be close to the second signal terminals 19. Accordingly,a circuit configuration in which the first signal terminals 18 areconnected to the signal electrodes 28 of the first semiconductor element20 a and a circuit configuration in which the second signal terminals 19are connected to the signal electrodes 28 of the second semiconductorelement 20 b are placed so as to be relatively distanced from eachother, thereby making it possible to easily manufacture thesemiconductor device 310, for example. Note that the first signalterminals 18 may be connected to the signal electrodes 28 of the firstsemiconductor element 20 a via bonding wires or other connection members(e.g., a circuit substrate). Alternatively, the first signal terminals18 may be directly connected to the signal electrodes 28 of the firstsemiconductor element 20 a. This also applies to the connection betweenthe second signal terminals 19 and the signal electrodes 28 of thesecond semiconductor element 20 b.

As illustrated in FIGS. 13A to 13D, the number and position of signalelectrodes 28 can be changed variously. In FIG. 13A, two gate signalelectrodes 28 a, two sense emitter electrodes 28 b, and one kelvinemitter electrode 28 c are provided as described above. On the otherhand, in a modification illustrated in FIG. 13B, two gate signalelectrodes 28 a and one kelvin emitter electrode 28 c are provided. In amodification illustrated in FIG. 13C, only two gate signal electrodes 28a are provided. In a modification illustrated in FIG. 13D, two gatesignal electrodes 28 a, two sense emitter electrodes 28 b, and twokelvin emitter electrodes 28 c are provided. In any of themodifications, the signal electrodes 28 a, 28 b, 28 c having the samefunction are placed bilaterally symmetrically. Further, various firstsemiconductor elements 20 a and various second semiconductor elements 20b as illustrated in FIGS. 13A to 13D can be also employed in thesemiconductor device 210 of Embodiment 3.

Embodiment 5

With reference to FIG. 14, the following describes a semiconductordevice 410 of Embodiment 5. The semiconductor device 410 of the presentembodiment is different from the semiconductor device 110 of Embodiment2 in that the intermediate conductor plate 32 is changed to a circuitsubstrate 432. The circuit substrate 432 is a direct bonded copper (DBC)substrate or a glass epoxy substrate, for example. The circuit substrate432 extends so as to pass through the sealing body 12. The first signalterminals 18 connected to the signal electrodes 28 of the firstsemiconductor element 20 a, the upper power terminal 14 connected to theupper conductor plate 30, and the intermediate power terminal 15connected to the front-surface electrode 24 of the first semiconductorelement 20 a are provided on a top face 432 a of the circuit substrate432. The second signal terminals 19 connected to the signal electrodes28 of the second semiconductor element 20 b, the lower power terminal 16connected to the lower conductor plate 34, and the intermediate powerterminal 15 connected to the front-surface electrode 24 of the secondsemiconductor element 20 b are provided on a bottom face 432 b of thecircuit substrate 432.

The semiconductor device 410 of the present embodiment has a functionand advantages similar to those of the semiconductor device 110 ofEmbodiment 2. In addition, since the circuit substrate 432 is employed,various terminals such as the first signal terminals 18 and the secondsignal terminals 19 can be provided together on the circuit substrate432. This makes it possible to more easily manufacture the semiconductordevice 410, for example.

Embodiment 6

With reference to FIG. 15, the following describes a semiconductordevice 510 of Embodiment 6. The semiconductor device 510 of the presentembodiment is different from the semiconductor devices 10, 110, 210,310, 410 of the above embodiments in that a common signal terminal 518is provided. The common signal terminal 518 is connected to the signalelectrodes 28 of the first semiconductor element 20 a and the signalelectrodes 28 of the second semiconductor element 20 b. By employing thecommon signal terminal 518, the sum of signal terminals 18, 19, 518 canbe reduced.

The common signal terminal 518 can be easily employed in thesemiconductor device 110 of Embodiment 2 and the semiconductor device310 of Embodiment 4, for example. In the semiconductor devices 110, 310,the second semiconductor element 20 b is placed such that the secondsemiconductor element 20 b is reversed back-to-front from the firstsemiconductor element 20 a. Accordingly, at least one of the signalelectrodes 28 of the first semiconductor element 20 a and at least oneof the signal electrodes 28 of the second semiconductor element 20 b mayface each other. In some embodiments, the common signal terminal 518 maybe employed for the signal electrodes 28 facing each other as such. Notethat the common signal terminal 518 can be typically employed for two ormore signal electrodes 28 (e.g., the aforementioned gate signalelectrodes 28 a) having the same function.

Embodiment 7

With reference to FIGS. 16, 17, the following describes a semiconductordevice 610 of Embodiment 7. The semiconductor device 610 of the presentembodiment is different from the semiconductor device 10 of Embodiment 1in that the number of first semiconductor elements 20 a and the numberof second semiconductor elements 20 b are changed. In the semiconductordevice 610, two first semiconductor elements 20 a are provided betweenthe upper conductor plate 30 and the intermediate conductor plate 32,and two second semiconductor elements 20 b are provided between theintermediate conductor plate 32 and the lower conductor plate 34. Notethat the semiconductor device 610 may include three or more firstsemiconductor elements 20 a. Further, the semiconductor device 610 mayinclude three or more second semiconductor elements 20 b. The number offirst semiconductor elements 20 a and the number of second semiconductorelements 20 b may be the same or may be different from each other. Whenthe number of first semiconductor elements 20 a and/or the number ofsecond semiconductor elements 20 b is increased, a current flowingthrough each of the semiconductor elements 20 a, 20 b is reduced.Hereby, a rated current (allowable current) of the semiconductor device610 can be raised.

Embodiment 8

With reference to FIGS. 18, 19, the following describes a semiconductordevice 710 of Embodiment 8. The semiconductor device 710 of the presentembodiment is different from the semiconductor device 10 of Embodiment 1in that the number of first semiconductor elements 20 a and the numberof second semiconductor elements 20 b are changed, and three firstsemiconductor elements 20 a and three second semiconductor elements 20 bare provided. Further, the intermediate conductor plate 32 in Embodiment1 is divided into three intermediate conductor plates, i.e., a firstintermediate conductor plate 732 u, a second intermediate conductorplate 732 v, and a third intermediate conductor plate 732 w. A firstintermediate power terminal 715 u is connected to the first intermediateconductor plate 732 u, a second intermediate power terminal 715 v isconnected to the second intermediate conductor plate 732 v, and a thirdintermediate power terminal 715 w is connected to the third intermediateconductor plate 732 w.

In the semiconductor device 710, one of the first semiconductor elements20 a is provided between the upper conductor plate 30 and the firstintermediate conductor plate 732 u, and one of the second semiconductorelements 20 b is provided between the first intermediate conductor plate732 u and the lower conductor plate 34. Further, another one of thefirst semiconductor elements 20 a is provided between the upperconductor plate 30 and the second intermediate conductor plate 732 v,and another one of the second semiconductor elements 20 b is providedbetween the second intermediate conductor plate 732 v and the lowerconductor plate 34. Further, a third one of the first semiconductorelements 20 a is provided between the upper conductor plate 30 and thethird intermediate conductor plate 732 w, and a third one of the secondsemiconductor elements 20 b is provided between the third intermediateconductor plate 732 w and the lower conductor plate 34.

The semiconductor device 710 of the present embodiment substantially hassuch a circuit structure that three semiconductor devices 10 ofEmbodiment 1 are connected in parallel to each other. As describedabove, the semiconductor device 10 of Embodiment 1 has a circuitstructure in which two RC-IGBTs are serially-connected between the upperpower terminal 14 and the lower power terminal 16 and the intermediatepower terminal 15 is connected between the two RC-IGBTs. Thesemiconductor device 10 can constitute upper and lower arms in a powerconverter circuit such as a DC-DC converter or an inverter, for example.Accordingly, the semiconductor device 710 of the present embodiment hasa circuit structure of a three-phase inverter, by itself. Note that, inthe semiconductor device 710 of the present embodiment, each of thefirst semiconductor elements 20 a may be changed to a plurality of firstsemiconductor elements 20 a. Similarly, each of the second semiconductorelements 20 b may be changed to a plurality of second semiconductorelements 20 b. Hereby, a current flowing through each of thesemiconductor elements 20 a, 20 b is reduced, and a rated current(allowable current) of the semiconductor device 710 can be raised.

Embodiment 9

With reference to FIGS. 20, 21, the following describes a semiconductordevice 810 of Embodiment 9. Similarly to the semiconductor device 10 ofEmbodiment 1, the semiconductor device 810 of the present embodimentincludes the first semiconductor element 20 a, the second semiconductorelement 20 b laminated to the first semiconductor element 20 a, and thesealing body 12 configured to seal the first semiconductor element 20 aand the second semiconductor element 20 b. Further, the semiconductordevice 810 includes the first signal terminals 18 connected to thesignal electrodes 28 of the first semiconductor element 20 a, and thesecond signal terminals 19 connected to the signal electrodes 28 of thesecond semiconductor element 20 b. When the first signal terminals 18and the second signal terminals 19 are planarly viewed along thelaminating direction (the Z-direction) of the first semiconductorelement 20 a and the second semiconductor element 20 b, the first signalterminals 18 and the second signal terminals 19 project from the sealingbody 12 toward the first direction (the X-direction) and are distancedfrom each other in the second direction (the Y-direction) that isperpendicular to the first direction (the X-direction).

In the meantime, the semiconductor device 810 of the present embodimentis different from the semiconductor device 10 of Embodiment 1 in thatthe configuration of the first semiconductor element 20 a and the secondsemiconductor element 20 b is changed. That is, in the presentembodiment, the semiconductor element 20 a, 20 b includes five signalelectrodes 28. The five signal electrodes 28 are arranged in line alongone side 21 s of the semiconductor element 20 a, 20 b. Along with this,the number of first signal terminals 18 and the number of second signalterminals 19 are also changed to five. Note that the number of signalelectrodes 28 and the number of the signal terminals 18, 19 are notlimited to five as long as at least two signal electrodes 28 arearranged in line along the one side 21 s of the semiconductor element 20a, 20 b.

Further, the semiconductor device 810 of the present embodiment isdifferent from the semiconductor device 10 of Embodiment 1 in that theorientations of the first semiconductor element 20 a and the secondsemiconductor element 20 b are changed. More specifically, the firstsemiconductor element 20 a is placed so as to be rotated by 45 degreesin one direction, and the second semiconductor element 20 b is placed soas to be rotated by 45 degrees in an opposite direction to the onedirection. Hereby, the one side 21 s of the semiconductor element 20 a,20 b is not parallel to one side surface 12 s of the sealing body 12,and forms an angle of 45 degrees with respect to the one side surface 12s. Here, the one side 21 s of the semiconductor element 20 a, 20 b is aside along which the signal electrodes 28 are arranged. The one sidesurface 12 s of the sealing body 12 is a surface from which the firstsignal terminals 18 and the second signal terminals 19 project. That is,in the semiconductor device 810 of the present embodiment, thearrangement direction of the signal electrodes 28 in the semiconductorelement 20 a, 20 b forms an angle of 45 degrees with respect to thearrangement direction of the signal terminals 18, 19 projecting from thesealing body 12.

Similarly to the semiconductor device 10 of Embodiment 1, in thesemiconductor device 810 of the present embodiment, the secondsemiconductor element 20 b is placed at an angle of 90 degrees shiftedfrom the first semiconductor element 20 a. Hereby, the signal electrodes28 of the first semiconductor element 20 a and the signal electrodes 28of the second semiconductor element 20 b are placed at differentpositions in terms of the arrangement direction (the Y-direction) of thesignal terminals 18, 19. The signal electrodes 28 of the firstsemiconductor element 20 a are provided so as to be closer to the firstsignal terminals 18 than to the second signal terminals 19, and thesignal electrodes 28 of the second semiconductor element 20 b areprovided so as to be closer to the second signal terminals 19 than tothe first signal terminals 18. With such a configuration, even in a casewhere the first semiconductor element 20 a and the second semiconductorelement 20 b are provided in a laminated manner, the first signalterminals 18 and the second, signal terminals 19 connected to the firstsemiconductor element 20 a and the second semiconductor element 20 b,respectively, can be placed so as to be distanced from each other. Sincethe first signal terminals 18 and the second signal terminals 19 do notoverlap with each other, the first signal terminals 18 can be easilyconnected to the signal electrodes 28 of the first semiconductor element20 a, and the second signal terminals 19 can be easily connected to thesignal electrodes 28 of the second semiconductor element 20 b.Accordingly, the configurations of the first signal terminals 18 and thesecond signal terminals 19 can be made simple. Further, since the firstsignal terminals 18 and the second signal terminals 19 are distancedfrom each other, it is possible to restrain electromagnetic interference(so-called noise) that can occur between the first signal terminals 18and the second signal terminals 19.

Particularly, in the semiconductor device 810 of the present embodiment,the first semiconductor element 20 a is rotated to the one direction soas to be placed diagonally. Hereby, the first signal terminals 18connected to the first semiconductor element 20 a can be placed, in abiased manner, on a first side of the one side surface 12 s of thesealing body 12. Similarly, the second semiconductor element 20 b isrotated to the opposite direction so as to be placed diagonally. Hereby,the second signal terminals 19 connected to the second semiconductorelement 20 b can be placed, in a biased manner, on a second side of theone side surface 12 s of the sealing body 12. Further, since the signalelectrodes 28 of the first semiconductor element 20 a and the signalelectrodes 28 of the second semiconductor element 20 b do not overlapwith each other, the first signal terminals 18 or the second signalterminals 19 can be easily connected to their corresponding signalelectrodes 28.

Note that the first signal terminals 18 may be connected to the signalelectrodes 28 of the first semiconductor element 20 a via bonding wiresor other connection members. Alternatively, like the present embodiment,the first signal terminals 18 may be directly connected to the signalelectrodes 28 of the first semiconductor element 20 a. Similarly, thesecond signal terminals 19 may be connected to the signal electrodes 28of the second semiconductor element 20 b via bonding wires or otherconnection members. Alternatively, like the present embodiment, thesecond signal terminals 19 may be directly connected to the signalelectrodes 28 of the second semiconductor element 20 b.

As understood from the above description, in the semiconductor device810 of the present embodiment, the first semiconductor element 20 a andthe second semiconductor element 20 b have the same configuration andinclude respective signal electrodes 28 arranged in line. Thearrangement direction of the signal electrodes 28 in the firstsemiconductor element 20 a and the arrangement direction of the signalelectrodes 28 in the second semiconductor element 20 b form an angle of45 degrees with respect the second direction (the Y-direction), However,this angle is not limited to 45 degrees and may be other angles such as30 degrees or 60 degrees, for example. At this time, the arrangementdirection of the signal electrodes 28 in the first semiconductor element20 a and the arrangement direction of the signal electrodes 28 in thesecond semiconductor element 20 b may not be parallel to each other andmay form different angles with respect to the second direction (theY-direction).

The structure described in the present embodiment, particularly, thestructure in which the semiconductor element 20 a, 20 b is placeddiagonally, may be employed only for one of the semiconductor elements20 a, 20 b. Alternatively, this structure can be effectively employed inother semiconductor devices including a single semiconductor element.When the arrangement direction of signal electrodes in a semiconductorelement forms an angle of 30 degrees, 45 degrees, 60 degrees, or thelike with respect to the arrangement direction of signal terminalsconnected to the semiconductor element, the signal terminals can beplaced, in a biased manner, at a desired position in a sealing bodywithout or extending or complicating the signal terminals.

FIG. 22 schematically illustrates a configuration of a semiconductordevice 810′ of one modification. The semiconductor device 810′ isdifferent from the semiconductor device 810 of Embodiment 9 in that thefirst semiconductor element 20 a or the second semiconductor element 20b is further rotated by 90 degrees, so that the second semiconductorelement 20 b is placed with a posture rotated by 180 degrees from thefirst semiconductor element 20 a. In this case, while the first signalterminals 18 connected to the first semiconductor element 20 a projectfrom the one side surface 12 s of the sealing body 12, the second signalterminals 19 connected to the second semiconductor element 20 b mayproject from a side surface 12 t of the sealing body 12 on the oppositeside from the one side surface 12 s. With such a configuration, thedistance between the first signal terminals 18 and the second signalterminals 19 can be made larger without complicating the structures ofthe first signal terminals 18 and the second signal terminals 19.

Some specific examples of the disclosure have been described in detail.However, the examples are for illustration only and do not limit thescope of the claims. The technique described in the scope of the claimsincludes the foregoing examples with various modifications and changes.Technical elements described in the present specification or thedrawings exhibit a technical usability solely or in variouscombinations.

What is claimed is:
 1. A semiconductor device comprising: a firstsemiconductor element including a first signal electrode; a secondsemiconductor element including a second signal electrode, the secondsemiconductor element being laminated on the first semiconductorelement; a sealing body configured to seal the first semiconductorelement and the second semiconductor element; a first signal terminalconnected to the first signal electrode; and a second signal terminalconnected to the second signal electrode, wherein: the first signalterminal and the second signal terminal project from the sealing bodyand extend in a first direction; the first signal terminal and thesecond signal terminal are distanced from each other in a seconddirection, the second direction being a direction perpendicular to thefirst direction and a laminating direction of the first semiconductorelement and the second semiconductor element; the first signal electrodeand the second signal electrode are placed at different positions in thesecond direction; the first signal electrode is provided closer to thefirst signal terminal than to the second signal terminal; and the secondsignal electrode is provided closer to the second signal terminal thanto the first signal terminal, wherein: the first semiconductor elementand the second semiconductor element have the same configuration, thesecond semiconductor element is placed at an angle 90 degrees shiftedfrom the first semiconductor element, at least one signal electrode of aplurality of signal electrodes is provided closer to one corner partthan to the other corner parts among four corner parts of the firstsemiconductor element, the signal electrodes being included in the firstsignal electrode, and all the signal electrodes included in the firstsignal electrode are provided closer to the one corner part than to theother corner parts among the four corner parts of the firstsemiconductor element.
 2. The semiconductor device according to claim 1,wherein: the second semiconductor element is provided such that thesecond semiconductor element is reversed back-to-front from the firstsemiconductor element.
 3. The semiconductor device according to claim 1,wherein the at least one signal electrode provided closer to the onecorner part than to the other corner parts is provided symmetricallywith respect to a bisector of the one corner part.
 4. The semiconductordevice according to claim 1, further comprising a power terminalelectrically connected to the first semiconductor element, wherein thepower terminal is placed on an opposite side from the first signalterminal across the sealing body.